A welding wire for automatic welding machines is provided in coils which each are placed in a container. A cover is provided on the container to prevent that dirt or any other contaminations reach the interior of the container. The cover normally is made of cardboard or plastic.
In order to be able to continuously feed the welding wire to the welding machine, it is known to use two containers, in fact a first container which currently provides the welding wire, and a second container which is employed as soon as the wire from the first container is completely used up. The end of the welding wire of the first container is connected with the start portion of the welding wire of the second container, so that a continuous feeding of the welding wire is ensured. When the first container is empty and the welding wire is withdrawn from the second container, the first container is replaced by a new one, and the start portion of the welding wire of the new container is connected with the end portion of the welding wire of the container which is currently employed.
It is important for the proper function of such a system that the welding wire does not entangle or develop kinks, in particular when the welding wire of a container has been used up almost completely so that the short residual portion of the welding wire is withdrawn from the container. With known systems, there isn't provided any cover on the container in order to ensure a proper changeover from one container to the other. Using an open container, however, results in soiling the welding wire.
PCT publication WO 02/094493 shows a system including two containers, in which a rider is disposed on the welding wire. The rider is a solid body and is supposed by means of its weight to avoid any kinks in the wire. It has been found, however, that this solution does not work satisfactorily.
It is the object of the invention to provide a cover for a welding wire container, which prevents an entangling of the welding wire or kinks in it, especially in case the system changes over from one container to the other, while it is made possible at the same time to use a cover for closing the container.